Controller.



No- 828,388. PATENTED'AUG. 14, 1906.

A. L. GUSHMAN.

CONTROLLER. APPLICATION FILED MAY3, 1905.

Win/66995: 700610602 91.9 xflel; Gag/emu,

PATENTED AUG. 14, 1906.

A. L. GUSHMAN.

CONTROLLER. APTLIOATION FILED MAYS, 1905.

, 3 SHEETS-SHEET 3.

JPe

. auaipiizdvfl UNITED 2133- PATENT oFFIcE- CONTROLLER.

No. 828,388. I

Specification of Letters Patent.

Patented Aug. 14, 1906. 7

Application filed May 3, 1905.- Serial No. 258,677-

To all whom it may concern:

and useful Improvements in Controllers, of

whichthe following is a specification.

My invention relates to controllers for variable-speed motors of the kind comprising a rheostat and control-levers for successively cutting out the armature resistances and cutting in the field resistances gradually to I increase the speed of the motor to its maxi mum and for cutting out the field resistances and cutting in the armature resistances gradu'ally to reduce the speed. It is of highest' importance in the use of variable-speed motors, particularly when employed to drive lathes, machine-tools, and the like, that the variable-speed resistances should all be operated by a single controllever or handle instead of by several handles, so that the attention and hands of the operator shall be diverted as little as possible from hiswork, also that in case the motor-current shall for any cause be interrupted the armature-lever shall immediately go automatically to off. posi tion, also that it shall be impossible to start the motor bythe o eration of the control-lever until the fieldevershall also have been returned to off position, which will always insure a strong field at starting; otherwise if themotor were started up with a weak field -sparking would result.

To accomplish the foregoing objects and otherwise to improve and simplify the-construction and operation of such rheostats or controllers, I have devised an electromechanical apparatus in which a single operating handle or lever operates both the armaturecontrol mechanism and field-coritrol mechanism, first to place the armature-control mechanismin cut-out or short-circuit position, where it is automatically locked, and then to operate the field-control mechanism independently. In what I believe to be the best form of my invention the single operating-lever is an extension of the field-lever, and

the armature-lever is locked thereto until the armatnrlever reaches the position to cut out all of the armature-resistances. Thereupon means for locking the armature-lever in cut-out position and unlocking the levers fromeach other, consistin of an electromagnet in shunt-circuit wit the motor, op-

crates latches, .so that if the motor-circuit is [interrupted the electromagnet will be deenergized, releasing the latch which locksthe armature-lever in cut-out position, which permits the same tofiy back to off position under the influence of a spring. .Fue thermore, as the armature-lever is forwardly operated only by the field-lever and handle the armature-control mechanism cannot be again operated after it has gone to off position without moving the field-lever and op erating-handle, so as to lock the levers together. This can be accomplished only by returning the field-lever to its off position. The motor is therefore necessarily next started up with a strong field.

Other features will hereinafter be pointed out.

my invention is in a rheostat for controlling a variable speed motor used for driving lathes, machine-tools, and the like, which has ver. Fig. 4 is a bottom view of the field-con trol lever. Fig. 5 is a side view of the armature-control lever. Fig. 6 is a side view of the field-control lever. Fig. 7 .is a plan view of the pole-changer, and Fig. 8 is a side View of the pole-changer.

Referring to the drawings, A represents a plate made of slate or other suitable material, u on which are mounted the rheostat and other. controller parts. a b c d, &c.,illustrate aset of armature-consistances, and a b c d, &c.,illustrate fieldcontacts connected, as usual, by field resistances.

Fixed near the middle of the plat'efA isa stud a upon which is mounted the arm or, lever a carrying the-carbon block a, adapted to travel over the contacts a b c d,.&c.

The arm a which will hereinafter be called is a bottomview of the armature-control le-- As one of the most useful adaptations of to be frequently reversed, I will address my tacts connected, as usual, by armature recooperate with the contact a, fixed to the plate A, to make and break the electromagnet-circuit, as will presentlybe described. A lever a is also mounted upon the stud of, provided with an extension e flwhich is coincident with the armature-lever 0. when the levers are locked together, as shown in Fig. 1. The lever a constitutes the field-lever and carries at its end the contact a, which travels overithe field-contacts a b c d,c&c. Mounted upon extensiondever'a is a handle a, by Wl'l1(3h the entire controller is operated. At the end of extension a is a shoulder e to cooperate with a latch 0., carried by the arm (1 The latch e is yieldingly held in operative position, as shown in Fig. 1, by a spring. (Not shown.)

Fixed to'the plate A is an electromagnet b whose armature I) is pivotally connected with the end of the arm b journaled to the plate A at b, as shown. "A spring 6 normally holds the arm 5 elevated against a stop I)", whereby it is normally in inoperative position.

A sprin at one en with the arm a and at its other end with the stud. a and normally tends to urge arm (15 toward its off position in the direction of the arrow in Fig. 1 and to hold the armature-lever a against a stop b The extension e and consequently the field-lever a, is normally locked, to the armaturelever a by means of the latch e and the stop 0 carried by the armature-lever a When the handle a is swung to the right in Fig. 1, it carries with it both the armature-' lever afland the field-lever a until the contact a engages the contact a and closes the circuit through the magnet 6 At that'fnoment the carbon contact a. of the armaturelever will have reached the last armature-- contact 1'. and all the armature resistances will have been cut out, thearmaturedever remaining in short circuit or cut-out position. The closing'of the circuit through electromagnet 5 causes the armature thereof b" to descend against the tailpiece a of the latch e thereby disengaging the latch from the shoulder a" and simultaneously operating the lever b until the latch or shoulder b passes into place behind a shoulder I)" on the end of the armature-lever, which holds the armature-lever in cut-out position and prevents it from returning to its off position un der the influence of spring 1)". While the two levers are being operated together and at the moment when the armaturedever has reached said cut-out position the field-lever will be in position to close the field-circuit through contact m, all the field resistances being cut out and the field being consequently strong. When the armature'lever my apparatus.

19 (shown in Fig. 1) is connected -25 to the other line-wire.

ceases reaches its cut-out osition, the operation of the latch a by t e electromagnet, as described, unlocks the two levers from each other and frees the field-lever to be operated by the handle a independently to cut in the field resistances through contacts a bf c d, &c. By thus weakening the field more or less as may be desired a very wide variation of. speeds may be attained. The armatureresistance contacts and the field-resistance contacts are so arranged with relation toeach other and'to the armature-lever and field-lever that contact a does not leave contact m until the magnet?) has operated to lock the armature-lever in cut-out positionand unlock the two levers from each other. 0 re resents a stop to limit the movement o the field-lever when the field resistances have all been cut in. n is a contact through which the field-circuit is first closed and is connected with the contact m by a fuse m to guard against unnecessary shocks when the motor is started.

I will now describe the electric circuits in The stud a is connected through wires 1 and 2 and binding-posts 3 with one line-wire. When annature-lever a engages with one of contacts a b c, &c., the armature-circuit through the mo tor M is made as follows: from such contact through the other contacts of the armature series and the armature resistances between them by wire 4 to bindingpost 5, thence by wire 6 to binding-post 7 of the pole-changer, thence by wire 8 to contact 9 of the pole-changer, thence through a bridge-piece 10,-contact 11, wire 12. to binding-post 13, thence by wire 1 k to the armature of the motor M, thence by wire 15 to binding-post 16 or" the pole-changer,

bridge-piece 19 to contact 20, and through wire 21 to binding-post 22 of the polechanger, thence by'wire 23 to a binding-post 24 of the rheostat, and thence through wire The field-circuit is from stud (1 through the fieldlever a to one of the field-contacts, thence by wire 26 to binding-post 27 of the rheostat, thence by wire 28 to the field of motor M, thence by wire 29 to the binding-post 30 of the poleehanger, thence by wire 31 to wire 21, and by wire 21 to line-wire by way of binding-post 24:. It will thus be seen that the field is in shunt-circuit.

From the foregoing it will be clear that after the armature-lever has reached its position to out out the armature resistances and has caused the two levers automatically to again out out automatically relocks the two levers together and unlocks the armature-lever from its cut-out position, so that the two levers may by the singlehandle be returned to OH position. This is effected as follows: The extension carries a stud c When during the movement of the handle a to the left in Fig. 1 the extension coincides with the armature-lever a", the stud c strikes the supplemental lever a pivoted to the armature-lever, and swings it away from contact a. Thereupon the circuit through the electromagnet b will be broken. The armature b of the electromagnet and the latch or lever 1 5 b are immediately lifted by spring I), causing the shoulder b to moveout of engagement with the shoulder b and the latch a simultaneously to be moved by its spring into engagement with the shoulder a. The two levers are thereupon again locked together and free to be moved to control the armaturecontacts, all under the control of the single operating-handle a In case the current should'be interrupted whilethe motor is running-with the armatore-lever in cut-out position and the field-lever on one of the field-contacts the magnet 11 will be denergized, permitting the arm b to be lifted by its spring, and thereby releasing the armature-lever from its cut-out position, from whence it will be automatically returned-to its off position by spring b Field- 'lever a will remain upon its field-contact one or more of the field resistances cut in,,and the field correspondingly weak; but I ,since the armature-lever is operated by the field-lever and 'both by a single operatinghandle before current can again be admitted to the motor the operating-handle must be moved to the left, Fig. 1, until latch (L13 springs behind shoulder a -and places the armature-lever again under-the control of the operating-handle. The field-lever 'will then have been moved into the position shown in Fig. 1, in which all the field resistances are cut out. When the motor is next started up, therefore, it will be with a strong field and will necessarily be so, since the single operating-handle by which the armature-lever can 20 v be controlled places the field-lever in cut-out position before it can again assume control of the armature-lever.

Each time the armature-lever returns to its off position the pole-changer (shown in Figs. 7 and 8) when used is operated to reverse the direction of the current to the armature,'so that when the motor is next started up it willoperate in reverse direction. The principal utility of this feature, as has been indicated, is in connection with drivingmotors for lathes'and the like, which have to be frequently reversed. The pole-changer is mounted on a suitable plate B. Fixed to the plate B is-a stud 41, upon which is rotatably mounted a wheel 42, of insulating material,

ing stud 41.

and a ratchet-wheel 43, the two Wheels rigidly connected together. Alongside of wheels, 42 and 43 a segmental armature 44 is also rotatably mounted on stud 41. The armature carries a pawl 45, which cooperates with the ratchet 43 and is: normally held elevated against the stop 46 by a spring 49,surround- The armature is actuated by electromagnet 39. Fixed to the plateB are the four contacts9, 11,-18, and 20, connected. 7 with the electrical conductors, as shown in Fig. 2. i I

The wheel or block 42 carries two conductors in the form of bridge-pieces 10 and 19, sov arranged that every quarter-turn of the wheel will change, the direction of the flow of the current through the armature-circuit above describedthat is, the bridge-pieces will alternately -connect contacts 18 and 9 with 20 and 11, respectively, and 18 and 20 with 9 and. 11, respectively. The magnet 39 is energized as follows:' Each time the armature lever a is returned to its ofi position with respect to the motor M con tact a engages with contact 35, Fig. 2. A 0. stop 5 is provided to limit the movement of the armature-lever and hold it at rest upon contact 35. Contact 35 is'connected by wire 36 with a hand-switch 37 which is connected by wire 38 with magnet 39. 5 Thence the circuit for magnet 39 is completed through wire 40, binding-post 30, wire 31, wire 21, binding-post 22, wire 23, bind-' ing-post 24, and wire 25 to the line-wire; Accordingly each time the foregoing circuit is closed by the engagement of the arma-. ture-lever with contact 35 the electromagnet 39 is energized and causes the segmental armature 44 to rotate a one-quarter turn in the direction indicated by the full-line arrow. A stop 48 is providedv to liinit the extent of such rotation. As it rotates the pawl 45 engages the ratchet-wheel 43, turning the wheel 42 and the bridge pieces 10 and 19 a quarter-turn.

WVhen armature-lever a is again moved away from contact 35 to start up the motor, magnet 39 is deenergized and armature 44 is automatically returned to its elevated position against. stop 46 by the spring 49 on stud 41.

When it is not desired to have the motor reverse after each movement of the controllever to its off position, the hand-switch 37 is opened, and the pole-changer is thereby me put out of service. i

The detail construction of the contacts 9, 11, 18, and 20 of the polewhanger is best shown in Fig. 8. Each comprises two spring-jaws 50, provided with sockets 52, holding the oontact pieces proper, 18, &c. Said contact-pieces are preferably made of carbon. The ends of the metal bridgepieces 10 and 19 pass between the carbon' contacts when the pole-changer is operated. 1 d

hat I claimis 1. A controller comprising an armaturecontrol mechanism, and a field control mechanism; the former requiring to be placed in position to cut out the armature resistances before the latter can be placed in position to cut in the field resistances; and means electrically actuated by the motor-circuit for automatically locking the arrnaturecontrol mechanism in its cut-out position.

2. A controller comprising armature resistances and field resistances; an armaturecontrol lever and a fieldcontrol lever, adapted successively to cut out the armature resistances and to cut in the field resistances, said levers being locked together, and the field-lever cont-rolling the armature-lever excepting when the armature-lever is in 'posi tion to out out the armature resistances; means electrically actuated by'the motorcircuit automatically to lock the armaturelever when it'reaches its cut-out position; and automatic means simultaneously to unlock the two levers; and means controlled by the. field-lever a ain-sirnultaneously to 'lock 'said levers toget er, and to unlock said armature-lever from output-position.

3. A controller comprising armature resistances and fieldresistances; an armaturecontrol lever and a field-control lever, adapted successively to cut out the armature resistances and to out in the field resistances,.

said levers being locked together, and the field-lever controlling the armature-lever eX,

cepting when the armature-lever is in position to cut out the armature resistances; a lock to hold the armature-lever in cut-out position; and an electromagnet in shunt with the motor and controlled by the field-lever,

adapted simultaneously to actuate saidlock and to unlock the levers from each other;

4. A controller comprising armature resistances and field resistances; two controllevers, one for each set of resistances, adapted successively to cut out thearmature resistances and to cut in the field resistances, said levers being normally locked together v excepting when the armature-lever is 111 position to cut out the armature resistance, and the armature-lever being operated by.

the field-lever; electrically-actuated means automatically to hold the armature-lever in said cut-out position and Simultaneously to unlock the two levers from each other, wheresistances and to cut in the field resistances,

the field-lever controlling the armature-lever; means normally in operative position for locking thetwo levers together; means normally in inoperative position for locking the armature-lever in cut-out position; and means controlled by the field-lever comprising an electromagnet adapted to operate both of said locking means; a normally open circuit therefor and a switch controlled by the field-lever, whereby the forward movement of the field-lever will close said switch and cause the electromagnet to lock the armature in cut-out position and unlock said levers from each other, and the return movement of the field-lever will open said switch I to permit said levers again to be locked together and the armature-lever unlocked from cut-out position. I

6. A controller comprising armature resistances and field resistances; an armaturecontrol lever and a field-control lever adapted successively to cut out the armature resistances and to cut in the field resistances; and means for automatically locking the ar mature-lever in its cut-out position comprising a'latch, an electromagnet in shunt with the motor for operating the latch, and a supplemental switch carried by the armaturelever forcontrolling the electromagnet circuit, the armature-lever and the supplemental switch being controlled by the field-lever.

7. A controller comprising armature resistances and field resistances; an armaturelever and a field-lever adapted successively to cut out the armature resistances and to cut in the field resistances, said levers being locked together and the field-lever controlling the armature-lever excepting when the armaturedever is in cut-out position; a latch for locking'tlie armature-lever in cut-out position; an electromagnet in shunt with the.

motor 'fonoperating the latch; and means controlled by the field-lever in its forward movement for simultaneously causing the electromagnet to close said latch and to unlock said levers from each other when the armature-lever reaches cut-out position, and means controlled by the field-lever in its return movement for opening said latch and relocking said levers with each other after the field resistance have been cut out. i

, 8. A controller comprising armature resistances and field resistances adapted to be successively operated; an armaturelever and a field-lever normally locked togetherby a latch a latch normally in inoperative position to-lock the-armature-lever in cut-outpd IIO sition; an electroma net in a normally open circuit for operating 0th latches, a movable circuit-closer carried by the armature-lever adapted to close the electromagnet-circuit when the forward movement of the lever brings the armature-lever to its cut-out position whereby the field-lever may be operated independently; the return movement of the field-lever, after the field resistances have been cutout, being adapted to actuate saidmovable circuit-closer again to en said electromagnet-circuit, whereby bot levers maybe returned to their ofi position to gether. Q U y 9. A controller comprising an armaturecontrol mechanism, and a field-controlmechanism; a singlev control-lever for operating both mechanisms; provision whereby the.

initial forward movement of the control-lever will cause the armature-control mechanism to be placed in cut-out position and there locked, and the continued forward movement of the control-lever will independently operate the field-control mechanism; and provision whereby the armature-control mechanism will automatically return to ofi position, independently of the field-controlmechanism when the motor-circuit is interrupted, and whereby said armature-control mechanism can again be operated only upon manually returning the field-control mechanism to off position.

10. A controller comprising an armaturecontrol mechanism, and a field-control mech 'anism; a single control-lever for operating both mechanisms; provision whereby the initial forward movement of the control-lever will cause the armature-control mecham ism to be placed in cut-out position and there locked, and the oontinued'forward movement of the control-lever will-independently.

o erate the field-control mechanism to out'in t e resistances thereof, and whereby the initial return movement :ot the controldever will cut out the field resistances and then unlock the armature-controlmechanis m from cut-out position, and the continued return movement of the control-lever will carry both mechanisms together to off position; and provisionwhereby the armature-control mechanism will automatically return to off position independently of the field-control mechanism when the motor-circuit is interrupted, and whereby said armature-control mechanism can'again be operated only upon manually returning the f eld-control mechanism to off position. i

11. A controller. comprising armature resistances and lever, and held resistances and lever, the armature-lever being movable under the control of' the-field-lever:until the-- former reaches its cut-out position;-- means for automatically locking the armature-lever in out-out position', ,the field-leyer'being thereafter independently operable to'cutin ffieldl resistances; meansfcontrolled by the field-lever after the" field-resistances have been cut out for unlocking thearmaturelever from its cut-out posiiiien rid" placing it again under the control nt It afield-lever;

- and provision whereby" the armature-lever will automatically return to ofl position independently of the field-lever when the motor-' circuit is interrupted, and whereby said armature-lever can; again be operated only upon manually returning the field-lever to off position.

12. controller comprisingarmature resistances and field resistances; two levers,

one for each-set of resistances, adapted successively to cut out the armature resistances and to ciit in the field resistances, said levers being normally locked together excepting .when the armature-lever is in cut-out position; a single control-handle bywhich both levers are operated; automatic means to lock thearmature-lever in cut-out position and to unlockv the two levers from each other when said cut-out position is reached, where by thefieldlever may be independently operated;: automatiomeans controlled by said handle again to lock the two levers together and. tounlock the armature-lever from its flto off position.

13'. A controller comprising armature resistances and field resistances; an armaturecont' 'ol lever and-a field-control lever, adapted successively to cutout the armature resistances and to cut in the field resistances,- said levers being locked together, and the, j field-lever controlling the armature-lever except ng when the armature-lever is in position to out out the armature resistances;

means under the control of the field-lever to lock the armature-lever in cut-outposition and unlock said levers from each other, whereby the field-lever may be operated independently, and means under the control of the field-lever again to unlock said armaturelever from cut-out position and relock said levers together; and provision whereby the armature-lever will automatically return to off position independently of the field-leverf when the motor-circuit is. interrupted,-

and wherebysaid armature-levercan again be 0 erated only'uponmanually returning the eld-lever to off position. 14'. A controller comprising armature re-.' sistances and field resistances arranged about a common center and on different sides thereof; an armature-lever and a field-lever cut-out position after the field-lever has been 'returned to a position .to cut out the field reboth journaled at said center, the field-lever having an extension normally overlying the armature-lever; a handle upon said exten: sion for operating bothlevers; means normally lockingthe extension and the armature-lever together; and provision whereby the'initial forward movement'of the operating-handle Will cause the armature-lever to be placed in cut-out position and there auto matically locked, and automatically unlocked from the extension, and whereby the continued forward movement of the operatin -handle will independently operate the fie d-lever.

15. A controller comprising armature resistances and field resistances arranged about a common center and on different sides thereof; an armature-lever and a field-lever both journaled at said center, the field-lever having an extension normally overlying the armature-lever; a handle upon said extension for operating both levers; means normally locking the extension and the arm ture-lever together; provision whereby tile initial forward movement of the operatingwill independently operate the field-lever;

and ms ans whereby the return movement of .the operating-handle after the field resistances have been cutout will automatically relock the extension and the armature-lever together and unlock said armature-lever from cut-out position.

Signed by me at' Concord, New Hamp-v shire, this 27th day of April, 1905.

ABE L. CUSHMAN. l/Vitnesses:

VERA L. CAToN, ROBERT CUsHMAN. 

